Micromechanical Modeling of Polymer Modified Asphalt at Low Temperatures

摘要

Polymer modified asphalt (PMA) is treated as a two-phase composite material with polymer particles dispersed in an asphalte matrix. Christensen and Lo's three-phase sphere model is thus extended to a two-layer built-in model to evaluate paramets affecting the low temperature cracking resistance of a PMA mixtue. A distinctive characteristic of the propsoed model is that it can consider the effect of the PMA layer thickness on the mechanical properties when a PMA is used in an asphalt pavement. In addition, it can consider the effect of the polyme rparticle size distributions on the mechanical peratures of the PMA. Approaches which are beneficial to enhance the low temperature cracking resistance of a PMA mixture are suggested based on the calculated results.